From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin LaHaise Subject: Re: linux-next: build failure after merge of the aio tree Date: Thu, 4 Feb 2016 11:01:01 -0500 Message-ID: <20160204160101.GD16315@kvack.org> References: <20160127134024.0fababf6@canb.auug.org.au> <20160129113056.GP10826@n2100.arm.linux.org.uk> <20160204131959.6695c7bf@canb.auug.org.au> <20160204134142.GA16315@kvack.org> <20160204135056.GE10826@n2100.arm.linux.org.uk> <20160204140822.GB16315@kvack.org> <20160204141253.GF10826@n2100.arm.linux.org.uk> <20160204143204.GC16315@kvack.org> <20160204143907.GG10826@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20160204143907.GG10826@n2100.arm.linux.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Russell King - ARM Linux Cc: Stephen Rothwell , Geert Uytterhoeven , Linux-Next , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" List-Id: linux-next.vger.kernel.org On Thu, Feb 04, 2016 at 02:39:07PM +0000, Russell King - ARM Linux wrote: > However, this one should warn: > > int test_wrong(char **v, const char **p) > { return __get_user(*v, p); } > > Good luck (I think you'll need lots of it to get a working solution)! :) This works with your test cases on x86-32. Note that it's only compile + link tested at present. -ben -- "Thought is the essence of where you are now." diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 09b1b0a..d8834c2 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -326,7 +326,21 @@ do { \ } while (0) #ifdef CONFIG_X86_32 -#define __get_user_asm_u64(x, ptr, retval, errret) (x) = __get_user_bad() +#define __get_user_asm_u64(x, addr, err, errret) \ + asm volatile(ASM_STAC "\n" \ + "1: movl %2,%%eax\n" \ + " movl %3,%%edx\n" \ + "2: " ASM_CLAC "\n" \ + ".section .fixup,\"ax\"\n" \ + "3: mov %4,%0\n" \ + " xorl %%eax,%%eax\n" \ + " xorl %%edx,%%edx\n" \ + " jmp 2b\n" \ + ".previous\n" \ + _ASM_EXTABLE(1b, 3b) \ + : "=r" (err), "=A"(x) \ + : "m" (__m(addr)), "m" __m(((u32 *)addr) + 1), "i" (errret), "0" (err)) + #define __get_user_asm_ex_u64(x, ptr) (x) = __get_user_bad() #else #define __get_user_asm_u64(x, ptr, retval, errret) \